Train it, and get it to Lvl 35 to evolve it to Weezing.
Koffing evolves into Weezing at level 35.
Koffing evolves into Weezing at Level 35
Koffing evolves into Wheezing, starting at level 35.
In Pokémon FireRed, Koffing evolves into Weezing when it reaches level 35. To evolve Koffing, simply train it in battles to gain experience points until it reaches the required level. Once it hits level 35, Koffing will automatically evolve into Weezing.
Koffing evolves according to level, it will start its attempt to evolve once it reaches Level 35.
Koffing evolves into Weezing at level 35
Koffing evolves into Weezing at level 35 in Pokémon FireRed. James uses a Koffing in the anime.
Koffing evolves at Level 35 in Pokémon Ruby.
34-38
level, 34.
Koffing evolves at level at level 35 into Weezing.
It evolves into Weezing by leveling it to 35.